Tray denesting device



United States Patent William D. Stockdale [72] Inventor Arlington Heights, Illinois [21 Appl. No. 764,447 [22] Filed Oct. 2, 1968 [45] Patented Nov. 24, 1970 [73 Assignee Illinois Tool Works Inc.

Chicago, Illinois a corporation of Delaware [54] TRAY DENESTING DEVICE [56] References Cited UNITED STATES PATENTS 2,561,723 7/1951 Berger 221/298X 3,075,671 l/l963 McAlpine et al. 221/238 3,092,288 6/1963 Lakinsetal. 22l/298 Primary Examiner-Samuel F Coleman Attorneys- Robert W. Beart, Michael Kovac, Barry L. Clark and Jack R. Halvorsen ABSTRACT: A support and dispensing mechanism for a stack of nested rimmed container assemblies, and including opposed pairs of elements having relatively differential or compoundmovements disposed adjacent the bottom of the stack at spaced stack-supporting positions with one of said elements of each pair supporting the stack by underlying engagement with bottom most container rims and with other of said elements of each pair movable toward the stack for engagement between confronting surfaces of the bottommost container rims and the next adjacent lower container rims tending to separate the bottommost container assembly from the stack for dispensing the same while supporting the depleted stack by underlying engagement with the said adjacent lower container rims; and thereafter withdrawing the separating elements and returning the supporting elements to initial positions for a subsequent cycle ofoperation.

,TRAY DENESTING DEVICE The present invention is concerned with a mechanism for supporting a stack of nested rimmed container assemblies and for dispensing thebottommost container assembly from the stack.

An objectof the invention is to provide such a mechanism including opposed pairs of elements arranged with one element of each pair initially supporting thestack and with the other element of each pair movable to stack-supporting position while separating a bottommost container assembly therefrom for dispensing.

Another object of the invention is to provide a mechanism of the above type wherein the elements of each pair are operated in timed relationship such thatoppose'd elements of each pair move to a position permitting dispensing of the bottommost container assembly and then return to initial position for supporting the depleted stack upon withdrawal of the other opposed elements of each pair prior to a repeating cycle of dispensing.

A further object ofthe invention is to provide a mechanism of the above type wherein the opposed elements tending to separate a bottommost container assembly include cam surfaces tending to elevate the depleted stack above the bottommost container assembly to assist in stripping that bottommost container assembly from the stack for dispensing.

A still further object of the invention is to provide a mechanism of the above type wherein the opposed elements normally supporting the stack comprise pivoted bars and the opposed elements tending to separate a bottommost container assembly comprise reciprocating plates with projecting fingers.

The invention still further aims to provide a mechanism of the above type wherein the bars and plates are operated in timed relation from a rotating shaft which includes suitably shaped rotary cam means.

In the accompanying drawing: i

FIG. 1 is a perspective view showing the opposed pairs of elements with a stack of container assemblies supported thereby; I

FIG. 2 is a top plan view showing one side of the apparatus;

FIG. 3 is a fragmentary side elevation showing the cam means for oscillating the pivoted bars and the link mechanism for reciprocating the fingered plates and showing the pivoted bars in position supporting the stack;

FIG. 4 is a fragmentary view, similar to FIG. 3 but omitting the operating mechanism, showing the positionsof the bars and plates with the bottommost container assembly separated from the stack and ready for dispensing with the reciprocating fingered plate supporting the depleted stack;

FIG. 5 is a fragmentary view, similar to FIG. 4, showing the position of the pivoted bars releasing the bottommost container assembly for dispensing; and

FIG. 6 shows return of the pivoted bars to a position to support the depleted stack just prior to withdrawal of the reciprocating fingered plates from stack-supporting position to the initial position of FIG. 3.

With reference to FIG. 1, a nested stack S of container assemblies is shown in association with mechanism for supporting the stack and dispensing a bottommost container assembly therefrom. The container assemblies may take various forms, but as illustrated, each container assembly C includes a plurality of rows of small so-called portion packages 10 with rims l2 and with each package rim connected to adjacent package rims across the assembly which thus provides a traylike multiple package unit. Each traylike unit is to be separated from the stack and dispensed in properly oriented position for accurate placement on a tray conveying apparatus or the like for removing each separated container assembly for further processing, such as filling, closing and the like.

The apparatus is mounted on any suitable type of supporting base (not shown except for a side frame element 11 shown in FIG. 2) along the sides of which are mounted a pair of plates 14, 140 each having a plurality of spaced fingers 16 extending inwardly and in opposition to similar fingers on the other plate. Thesefingers are positioned so as to extend into the area between rims of bottom adjacent container assemblies in the stack when operated for dispensing a container assembly. Beneath the fingers on each plate, there is mounted a pivoted bar 17 with a centering formation at the edge to engage beneath the rims of the bottommost container assembly supporting the stack in that position.

As shown in FIG. 1, there is an input shaft extending into gear boxes 16, 16a with suitable gearing (not shown) to rotate the shafts 18, 19 counterclockwise and clockwise, respectively. Each shaft 18-, 19 is connected to a rotating element 20, 21, respectively, to which links 22, 23, respectively, are eccentrically connected. Also as shown in FIG. 1, the plate 14a is connected at opposite ends to bars 24,2411, the latter being connected to the link 23 and the former being connected to a similar link at the opposite end of the apparatus.

The gear boxes 26, 26a, plates 14, 14a, bars 17 and the driv ing mechanisms are in mirror image so that further details will be described with reference to FIG. 2 showing the plate 14 and its gear box 16 turned to the illustrated plan position. The link 22 is connected to the plate 14 by a bar 25 and a similar link 22a at the opposite end of the plate is connected to a bar 25a, both bars being connected to the plate 14 for reciprocating the same. The plate 14 is also guided by pairs of capped supports 27, 27a projecting through transverse slots 28 in the plate 14, thus confining the plate to reciprocating movement in accordance with the movement of the links 22, 22a and the bars 25, 25a. The shaft 18 extends from the rotary member 20 through the supporting base beneath the plate 14 to a similar rotary member 200 at the opposite end thereof. The bar 17 is disposed below the plate 14 and has stub shafts 32, 32a at opposite ends thereof with cam followers 34, 34afixed thereto and following the contours of cams 36, 36a, respectively, also mounted on the shaft 18 within the rotary elements 20, 20a, respectively. The bar 17 is recessed at intervals 40 to accept base mounted vertical rods 42 assisting in stabilizing the stack S. Further, it should be noted that the bar 17 has a recessed .ledge 17a along the free edge thereof. This serves to snugly receive the adjacent container assembly rims and center the assemblies for accurate dispensing to a conveyor or the like therebelow. Still further, it should be noted that the ends of the fingers 16 have upper and lower tapered surfaces providing wedgelike free ends 16a, the purpose of which will be referred to below.

In describing the operation for dispensing a bottommost container assembly and supporting the stack, reference will be made to FIGS. 3, 4, 5 and 6, it being understood that these FIGS. show the mechanism at one side of the stack but that the mirror image mechanism is simultaneously operating at the opposite side of the stack. In FIG. 3, the cam 36 is more clearly illustrated as including a high portion 36a and a low portion 36b. With the mechanism in the position shown in FIG. 3, the link 22 is at its rearmost position with the fingered plate 14 retracted from the stack. Also in this position of mechanism, the cam follower 34 is engaged with the high portion 36a of the cam 36 so that the oscillating bar 17 is in position with the lowermost rims resting on the ledge portions 17a supporting the stack. As the element 20 rotates, the link 22 will be drawn inwardly with the fingered plate reaching the position shown in FIG. 4 where the bar 17 has been lowered slightly but is still supporting the bottommost container assembly now stripped from the stack. During this stripping of the bottommost container, it will be noted that the wedge portions 16a of the fingers 16 will have engaged the confronting surfaces of the rims 12, 12a urging the rim 12a upwardly slightly, as illustrated, to effect a positive prying apart of these two lower container assemblies. Further rotation of the element 20 brings the cam follower 34 into engagement with the low portion 36b of the cam, thus further lowering the bar 17 to the position of FIGS where the bottommost container is now in free falling dispensing movement to an underlying conveyor or the like. Still further rotation of the element 20 will return the fingered plate 14 approximately to the position of FIG. 6

where the now depleted stack is temporarily supported at the free ends of the fingers 1'6 with the bar 17 returning to the initial position of HO. 3. Upon complete retraction of the fingered plate 14, the depleted stack will now drop and rest upon the ledge portions 17a which serve to center the now bottommost container for accurate further dispensing to an underlying conveyor or the like as the mechanism repeats its cycle of operation.

While one form of the invention has been shown for purposes of illustration, it is to be clearly understood that various modifications may be made without departing from the scope of the invention as set forth in the appended claims.

I claim:

1. Means for supporting a stack of nested container assemblies each having laterally projecting rims, and selectively removing a bottommost container assembly from the stack; and comprising opposed pairs of selectively operable elements disposed adjacent the bottom of the stack, the first element of each pair initially positioned to underlie rims of the bottommost container assembly for supporting the stack, the second element of each pair initially positioned retracted from the stack when supported on said first elements, and means operable to relatively shift said elements of each pair in timed relationship with each said second element of each pair moving inwardly between the bottommost rim and the next adjacent rim for engagement between the confronting surfaces thereof to separate the bottommost container assembly from the stack, and with each said first element of each pair progressively shifting away from the path of downward dispensing movement of the separated bottommost container assembly and then returning to underlie the bottommost rim supporting the depleted stack and with said second elements returning to the initial retracted positions thereof for a repeating cycle of operation, the first element of each pair comprising a pivoted bar with the free end thereof shaped to engage a bottommost rim with the stack in centered position for accurately dispensing the bottommost container assembly, and the edges of the bars being recessed to provide ledge portions snugly receiving the rims of the bottommost container assembly in stack-supporting position.

2. Means for supporting a stack of nested container assemblies as claimed in claim 1, wherein the second element of each pair comprises a reciprocating plate having wedge formations at the free edge thereof to pry apart the bottommost container assembly from the next adjacent container assembly in the stack.

3. Means for supporting a stack of nested container assemblies as claimed in claim 2, wherein the plate is provided with a plurality of spaced fingers having the wedge formations at the free ends thereof.

4. Means for supporting a stack of nested container assemblies as claimed in claim 1, wherein the first element of each pair comprises an oscillating bar and the second element of each pair comprises a reciprocating plate, and wherein the means for shifting the elements in timed relationship comprises cam and follower means for oscillating the bars and link means for reciprocating the plates.

5. Means for supporting a stack of nested container assemblies as claimed in claim 4, wherein the cam means and the link means are operated from a single shaft. 

